Close to 40% of US children are exposed to secondhand tobacco smoke (SHS) in homes and up to 50% in cars, compromising the health and lives of millions of children. More effective, inexpensive, and accessible interventions are needed that impact parents'and caregivers'willingness and ability to institute smoking restrictions. We propose the development of an innovative, computerized simulation intervention, SHS-Sims, that allows caregivers to see the extent to which their or others'smoking exposes children to SHS, the potential negative health impacts of the exposure, and how different actions can reduce the exposure. The heart of the intervention is an interactive screen depicting the simulation of SHS exposure, with appealing graphics, animation, sound, and audio communication in English and Spanish. In the proposed Phase I STTR, we will test the feasibility and potential merit of the intervention by recruiting a total of approximately 80 participants in Women, Infant, and Children (WIC) clinics, who allow smoking in their car and who will be randomly assigned to the SHS-Sims intervention or static educational control groups (~40 in each group). The computer intervention will involve the exploration of different real life scenarios with the simulation interface. Participants will be provided with user-friendly direction and explanation of exposures and health effects. At the end of the intervention, the subjects will be interviewed about what they learned, and about their intentions to change behavior. We will judge the success of the Phase I intervention by its ability to: (1) increase knowledge and understanding regarding SHS exposure and strategies to reduce exposure;(2) increase intentions to initiate mitigation strategies;and (3) be accepted by clinic staff. Data from Phase I will be used to determine the utility and appropriateness of developing a more extensive simulation-based intervention that focuses on other common avenues of SHS exposure, including the home and the outdoors. The proposed intervention technology has the potential to be of great public health significance in that it could be deployed widely and inexpensively to parents in waiting rooms of clinics, hospitals, or medical practices.